EP1181663 A1 discloses a portable reader. The reader comprises a part for electric connection to the port of a computer, whereby said part exhibits four conduction lines in addition to a part for the insertion of a module which is removable and which can store confidential information, comprising the body of a plastic module which is substantially parallelepiped and rectangular whereby the dimensions thereof are 25 mm long, 15 mm wide and 0.76 mm thick, further comprising an integrated circuit chip provided with contact pads which are electrically connected to contact pads which are flush with one of the surfaces of said module, whereby the insertion part comprises a connector which has pins which are electrically connected to the electric connection lines of the reader and, when the module is inserted into said reader, to the contact pads of said module. The portable reader is specifically designed for readers, which are to be connected electrically to a USB port in a computer.